Tara Parker-Pope writes in The New York Times about the conclusions of some medical researchers that long-distance running is a major evolutionary advantage for humans. The ability to remain cool by sweating instead of panting and a foot structure ideal for running helped early humans hunt:

Most mammals can sprint faster than humans — having four legs gives them the advantage. But when it comes to long distances, humans can outrun almost any animal. Because we cool by sweating rather than panting, we can stay cool at speeds and distances that would overheat other animals. On a hot day, the two scientists wrote, a human could even outrun a horse in a 26.2-mile marathon.

Why would evolution favor the distance runner? The prevailing theory is that endurance running allowed primitive humans to incorporate meat into their diet. They may have watched the sky for scavenging birds and then run long distances to reach a fresh kill and steal the meat from whatever animal was there first.

Other research suggests that before the development of slingshots or bows, early hunters engaged in persistence hunting, chasing an animal for hours until it overheated, making it easy to kill at close range. A 2006 report in the journal Current Anthropology documents persistence hunting among modern hunter-gatherers, including the Bushmen in Africa.[...]

There is other evidence that evolution favored endurance running. A study in The Journal of Experimental Biology last February showed that the short toes of the human foot allowed for more efficient running, compared with longer-toed animals. Increasing toe length as little as 20 percent doubles the mechanical work of the foot. Even the fact that the big toe is straight, rather than to the side, suggests that our feet evolved for running.

I guess you were referring to yourself when you said "Ah, to be an academic who relies on theory instead of personal experience."

Before 'theorizing' that it's impossible do some little research. Here's one for a start http://en.allexperts.com/e/p/pe/persistence_hunting.htm or this http://en.wikipedia.org/wiki/Persistence_hunting or this video http://www.google.com/url?sa=t&source=web&ct=res&cd=1&ved=0CAcQFjAA&url=http%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D9wI-9RJi0Qo&ei=iRkCS-XOFpC0lAegjtiYCw&usg=AFQjCNHIonjF-3tjaVG4U8FkdarLRI-RHw&sig2=dca2fYg5JpXhPfftCcX9iQ .

Machines, airplanes, and automobiles were MADE BY HUMANS. It's not like technology has always existed in the universe, and humans MAGICALLY (ie: divine intervention) appeared in the world able to "fit right into them".

You do realize humans came first.. right? We created cars... to FIT OUR BODIES. If we were shaped like octopuses, the cockpits in our airplanes would obviously be different, buddy.

Ronald Darwin has worked out the principle of unguided or undirected evolution. I merely seem to point here at the strong evidence of guided evolution- ney dare I say - guided and prethought development. Imagine- All that energy of about 15 billion years of planetary evolution and then about 1,5 billion years of evolution of life Júst sparked and corrected to make humans so perfect that they can use these cars and aeroplanes...! Incredible...! That whole bipedal walking-thing is just a moment in our development- a fad that soon will dissapear because now we are reaching our directed evolutionary destinies: Segway, Car and Aircraft.

Horses do not have to be trained to trot, they do it naturally. Endurance horses trot the vast majority of the 100 mile races as it's a very efficient gait.

Horses have 4 natural gaits: the walk, trot, canter and gallop. Foals will often trot within a couple days of birth.

IMHO horses should be considered an endurance animal rather than a sprint animal. When horses were the only means of transportation they were often expected to move all day (often at a trot) and were able to do it with little trouble.

I wish people would do some research before commenting. "Only superior to an inchworm." Really? Please.

This idea is taken from the book "Born to Run" by Christopher McDougall, which I just finished about a month ago. It was a great read, with a really in-depth look at the Tarahumara, a tribe of runners in Mexico's Copper Canyon. For anyone who is intrigued by this idea, McDougall makes a very convincing argument based on many, many sources.

Deer and other animals run quickly for short amounts of time, but humans can, and do, frequently run 100 miles or more in ultramarathons without stopping. Eventually that deer, tuckered out from constantly running away from a group of runners, will collapse to the ground. This hunting method is still used in parts of Africa.

The thing I hate most about blogs is how everyone thinks that their opinion, when completely unsupported by research, is a valid part of a discussion. It's not. It's actually irrelevant and obnoxious.